Descriptors for Electron and Hole Charge Carriers in Metal Oxides

Daniel Davies, Christopher Savory, Jarvist M. Frost, David O Scanlon, Benjamin Morgan, Aron Walsh

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Metal oxides can act as insulators, semiconductors, or metals depending on their chemical composition and crystal structure. Metal oxide semiconductors, which support equilibrium populations of electron and hole charge carriers, have widespread applications including batteries, solar cells, and display technologies. It is often difficult to predict in advance whether these materials will exhibit localized or delocalized charge carriers upon oxidation or reduction. We combine data from first-principles calculations of the electronic structure and dielectric response of 214 metal oxides to predict the energetic driving force for carrier localization and transport. We assess descriptors based on the carrier effective mass, static polaron binding energy, and Fröhlich electron–phonon coupling. Numerical analysis allows us to assign p- and n-type transport of a metal oxide to three classes: (i) band transport with high mobility; (ii) small polaron transport with low mobility; and (iii) intermediate behavior. The results of this classification agree with observations regarding carrier dynamics and lifetimes and are used to predict 10 candidate p-type oxides.
Original languageEnglish
Pages (from-to)438-444
Number of pages7
JournalJournal of Physical Chemistry Letters
Volume11
Issue number2
Early online date25 Dec 2019
DOIs
Publication statusPublished - 16 Jan 2020

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